As the components required to build a computer system have reduced in size, new categories of computer systems have emerged. One of the new categories of computer systems is the "palmtop" computer system. A palmtop computer system is a computer that is small enough to be held in the hand of a user. Most palmtop computer systems are used as addressbooks, daily organizers, and electronic notepads.
Since palmtop computer systems are so small, keyboards are generally not efficient input devices. Palmtop computers with keyboards have keyboards that are so small that a user cannot touch-type. Furthermore, to use a keyboard a user must usually put the palmtop computer system down onto a flat surface so the user can type.
Instead of using a keyboard, many palmtop computers employ a pen and a digitizer pad as an input system. The pen and digitizer pad combination works well for palmtop computers since the arrangement allows a user to hold the palmtop computer system in one hand while writing onto the digitizer pad with the other hand.
There have been a number of palmtop computer systems introduced that rely on the pen and digitizer pad combination as the primary means of interfacing with the computer system. Most of these pen-based palmtop computer systems provide handwriting recognition whereby the user can write words and letters on the digitizer pad and the palmtop computer system converts the user's handwriting into a machine readable format. Examples of pen-based palmtop computer systems that provide handwriting recognition include the Apple.RTM. Newton.RTM. and the Tandy.RTM. Zoomer.TM..
One of the major difficulties in designing a pen-based palmtop computer system is that handwriting recognition requires a large area in which to write. Although a user can comfortably view text on a computer screen displayed in a relatively small font, most users require a much larger surface area in order to write with a pen on a digitizer pad. A larger area is required for writing since digitizer pads are not extremely accurate and the resolution of most flat panel display devices is not great enough to display small ink patterns. However, a competing goal for palmtop computer systems is that users want the systems to be very small for portability. Thus, it would be desirable to design a palmtop computer system that minimizes the amount of surface area required for a handwriting area such that the amount of area on a small palmtop computer system used for the display screen is maximized.